Hubbard said it was science

He said it very clearly, and on many occasions. He compared his
"tech" with physics and chemistry, and said it was just as precise.
He said he was a nuclear physicist. He said
he'd done experiments and had evidence. He put an equation in
"Dianetics, the modern Science of Mental Health".

Hubbard did not know the first thing about science. Chapter one of
Dianetics is total proof of that, to a real scientist. (Nor is
that "equation" actually an equation - it just looks like one.) His
science fiction has terrible lapses of knowledge and logic. He did
study to be a mechanical engineer, but flunked out half way
through. He got 'F' in Nuclear Physics.

Of course, a lot of the lower-level tech is common sense, not
rocket science. And it is exactly that part that works. The rest of
the tech is pretty much Flat Earth.
"Touch assists" may have psychological benefit, but Hubbard's
explanations about "energy ridges" are out of bad 1930's science
fiction. Likewise, his explanations of "mental mass", the
Purification Rundown, exteriorization and the like. (Ask me for
details.) There has never been a demonstration of "OT superpowers".
And even the Church admits that most of the claims in Dianetics
are false. Clears do get colds: they still wear glasses: they
get old and die. They do not have high IQs or perfect recall. There
are no famous scientists (or chess grandmasters) who are Clear. What
kind of science would keep publishing claims that they admit are false?

So why do people buy in? Because much of the low level tech works
fine, but at something it isn't advertised as doing. It works as a
way to install a new belief system in the customer. Auditing with an
e-meter is biofeedback training. (Radio Shack sells biofeedback
meters for $15, not for $3,750.) Repetitive drills cause a hypnotic
trance state. Trance makes you more susceptible and more suggestible.
It easily gives "highs", and brief hallucinations such as
"exteriorization".

The "suppressive person" theory encourages you to explain your
personal troubles with a cheap band-aid: a scapegoat. And, of course,
you should "disconnect" from the scapegoat, so that other believers
become a bigger and bigger fraction of your personal world. In short,
it's not "religious technology": it's recruitment technology.

Who am I, to say such things?

The important thing is, can I back up what I said? Can I produce,
say, biochemistry texts contradicting Hubbard's claims about the
Purification Rundown? The answer is yes.

But if you insist on credentials: I have a Bachelors in Engineering
Physics, and a Ph.D. in Computer Science. Science fiction,
pseudoscience, and the philosophy of science, have been hobbies for a
few decades.